Can't drop lower unit on Tohatsu 6HP

[gallilaw]

I need to change the impeller on my 2-year-old Tohatsu 6HP SailPro.

I have the Service Manual and have followed the instructions.

I removed the rubber grommet and loosened the shift rod joint bolt, and the two rods can now move independently and freely.

I have removed the two gear case bolts.

I have tried many times to pull the gear case assembly down to gain access to the water pump, but each time it remains firmly attached, almost as if the drive shaft was bolted to the engine.

I can wiggle the gear cases assembly freely; I just can't get it to drop.

I have used my hand to slam it down, and have tapped it with a hammer, using some wood as a buffer to avoid metal-to-metal contact.

Because my SailPro is a long-shaft, there is a large cast spacer that connect the gear case assembly to the drive shaft housing. I have tried to free up the gear case assembly by disconnecting the bolts that hold the spacer in place. No change; the gear case assembly won't drop.

I have tried turning the engine to move the drive shaft but that doesn't help either.

I am afraid if I hit the gear case assembly any harder I will wreck the motor.

Any advice?

 

[TOHATSU GURU]

Re: Can't drop lower unit on Tohatsu 6HP

The two bolts and the shift rod bolt are it...

 

[pvanv]

Re: Can't drop lower unit on Tohatsu 6HP

Wedges and patience are required. The drive shaft may be stuck in the crank. That may be due to lack of grease on the splines, or it could even be a twisted drive shaft. The drive shaft passes through a stabilizing bushing inside the exhaust housing. If there is crud on the shaft, that can add significant resistance to pulling the shaft down. BTW, don't bother changing just the impeller. Do the complete wp kit. Pumps better, and lasts longer.

 

[gallilaw]

Re: Can't drop lower unit on Tohatsu 6HP

Finally got it apart. It took an unbelievable amount of force. I actually snapped a pry bar. Used a heavier pry bar, applied more force than I want to remember, and the drive shaft finally released. Put in a whole pump repair kit, not just the impeller.

After all the time and effort getting it apart, I forgot to care about the gear sync when I put it back together. Now all the parts are assembled and I don't know what direction the clutch cam is pointing, what gear it's in currently, or whether the cam rod and the shift rod are properly set up at the shift rod joint.

 

[pvanv]

Re: Can't drop lower unit on Tohatsu 6HP

You can test the gear coupler sync. See if the shift lever moves fully from F-N-R (you will need to turn the prop to engage R). If not, adjust the coupler. The cam wedge should not fit backwards.

Did you grease the drive shaft splines before reassembling?